The present invention relates to computerized tomography (CT), and in particular to a data acquired system (DAS) and a CT apparatus using the same.
A CT apparatus has been used for real time observation of the internal condition of an object. A typical CT apparatus includes an X-ray source configured to emit X-rays to a patient or luggage. A detector is installed on the other side of the object and configured to detect the X-rays passing through the object.
For instance, the CT apparatus measures a human body based on different absorption and penetration rates of different tissues for the X-rays, and then inputs the measured data into a computer which, after processing the data, can take a sectional or stereo image for the examined part of the body, thereby discovering tiny pathological changes of any part in the body.
A DAS is mainly used to receive the electrical signals acquired by the detector, and convert the signals into digital signals for subsequent processing. Certainly, the DAS is not limited to this use, and is sometimes employed in the subsequent processing. In some designs, the detector is directly integrated in the DAS.
U.S. Pat. No. 7,236,562 B2, which is hereby incorporated by reference in its entirety, discloses a method of assembly and thermal management of CT detector electronic circuits. FIGS. 1 and 2 of U.S. Pat. No. 7,236,562 B2 demonstrate the operating mode and principle of the CT apparatus and the DAS therein.
The DAS includes several circuit boards with electrical components. In the prior art, it is rather difficult to have uniform temperature distribution on different circuit boards and lower temperature on each circuit board.